The outstanding ability of nanosilica to stabilize dispersions of Nylon 6 droplets in a polypropylene matrix

Abstract

The effectiveness of hydrophobically modified nanosilica (NS) as interfacial modifying agent for immiscible polymer blends is evaluated. Blends of polypropylene (PP) with 20% of polyamide 6 (PA) and 5% hydrophobic NS were prepared by melt mixing. Compression molded sheets and extruded films were evaluated by scanning electron microscopy, transmission electron microscopy, tensile testing, and rheological measurements. Hydrophobic NS particles strongly reduce the polydispersity and droplet size of the dispersed phase, as a result of their preferential location at the interface. NS promotes outstanding stability of blend dispersion regardless of the processing or post-processing technique employed.The viscoelastic terminal zone shows a plateau for PP/PA/NS, which corresponds to a suspension-like behavior. Under large amplitude oscillatory shear, the increment in the non-linearity parameter Q evidences the interactions between NS and blend components. Therefore, NS is an excellent morphological stabilizer that prevents coalescence, but cannot promote interfacial adhesion between immiscible PP and PA phases. V C 2015

Polyethylene terephthalate/low density polyethylene/titanium dioxide blend nanocomposites: Morphology, crystallinity, rheology, and transport properties

“…The rheological properties determined by oscillatory flow measurements, have been widely investigated in the linear viscoelastic regime, focusing on the interfacial tension. Also in the nonlinear regime, but to a lesser extent, focusing on the relationship between droplet size and a nonlinearity parameter derived from Fourier analysis of the sinusoidal stress and strain . However, the properties under continuous flow have been scarcely analyzed for polymer blends containing fillers, currently called blend composites …”

“…6,7,[13][14][15] Also in the nonlinear regime, but to a lesser extent, focusing on the relationship between droplet size and a nonlinearity parameter derived from Fourier analysis of the sinusoidal stress and strain. [16][17][18][19] However, the properties under continuous flow have been scarcely analyzed for polymer blends containing fillers, currently called blend composites. 20 Regarding PET/polyolefin blends, some works have been reported for PET/PP blends containing TiO 2 .…”

Polipropileno/poliamida nahasteen konpatibilizazioa: azterketa morfologiko eta erreologikoa

“…Polimero horren aplikazio nagusiek automobilgintzan, industria elektronikoan, ehungintzan eta paketatzean dute eragina. Polipropilenoari poliamida gehitu zaio zenbait ezaugarri hobetzen dituelako, adibidez propietate mekanikoak, gasekiko iragazkortasuna eta egonkortasun termikoa [9][10][11].…”

“…Morfologia-aldaketa hori kargen kokapenari zor zaio, izan ere, nanosilika hori interfasean kokatzen da; horrela, PA tantak inguratzen ditu hesi fisiko bat eratuz. Modu horretan tanten koaleszentzia ekiditen da eta, ondorioz, tanten tamaina txikiagoa da [6,7,11,15]. Sarreran aipatu bezela, prozesaketan materialak fluxu desberdinak jasan ditzake morfologia eraldatuz; ondorioz, sistemaren ezaugarritzea oinarrizkoa da.…”

Effect of carbon nanotubes on morphology evolution of polypropylene/polystyrene blends: understanding molecular interactions and carbon nanotube migration mechanisms

“…16,18,19 The decrease of interfacial tension has been inferred from direct or indirect measurements, such as traditional continuum thermodynamics concepts, rheological calculations, theoretical calculations, and inferences from morphological renements. 9,[18][19][20] Ray et al 19 inspected the effect of clay on the morphology of polypropylene (PP)/polystyrene (PS) blends. Clay nanollers led to a compatibilization effect, described by the decrease of interfacial tension.…”